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Уважаемые коллеги!<br>
<br>
На заседании Ученого совета в пятницу 21 января в 11:30 будет
заслушан доклад:<br>
<br>
Inogamov N.A.<br>
<font size="4"><b>Equations of state (EoS), two white spots in EoS:
examples from laser ablation in liquid and from laser driven
mechanics of deformable solids</b></font><br>
<br>
Example 1. Uncertainties of EoS in the near-critical region.
Numerical modeling of ablation into a liquid has been performed.
Molecular dynamics and hydrodynamics codes have been applied. Laser
radiation passes through a transparent liquid and illuminates a
metal target. Absorption and reflection of light from the target
takes place. The range of absorbed energies about 1 J/cm2 of
interest for technology is considered: below these values few
nanoparticles (NPs) are formed per laser pulse, above - optical
breakdown of the liquid takes place. A theory has been developed
which, using simulation data and thermodynamic information
(equations of state of matter), makes it possible to estimate the
mass and composition of NPs formed by laser impact.<br>
[1] N. A. Inogamov, V. V. Zhakhovsky, V. A. Khokhlov, "Physical
processes during laser ablation into a liquid", Pisma v ZhETP,
115(1), 20-27 (2022).<br>
<br>
Example 2. Uncertainty of the EoS state associated with
elastic-plastic phenomena in solids. It is necessary to describe
both elastic characteristics and supercritical fluid at the same
time.<br>
Powerful laser exposure causes irreversible changes in the crystal
structure of the target. These changes are the basis of laser shock
peening (LSP) technologies. The processes determining the thickness
of the residual strain layer and related residual stresses are
investigated in this work. It is known that the termination of
pinning is associated with the attenuation of the laser shock wave.
In this work, new information was obtained concerning the
transformation of the wave from elastic-plastic to elastic mode of
propagation in the case of picosecond impact. The elastic wave is
useless for pinning. It turns out that during the transformation,
the classical configuration with the plastic jump and the elastic
precursor before it disappears. In this case, the leading edge of
the expanding plastic layer gradually reduces its speed below the
volume speed of sound, smears inside the rarefaction wave and stops.
While the elastic system of waves is very important for the modern
laser opto-acoustics applications.<br>
[2] N. A. Inogamov, E. A. Perov, V. V. Zakhovsky, V. V. Shepelev, Y.
V. Petrov, S. V. Fortova, "Laser Shock Wave: Plasticity, Residual
Deformation Layer Thickness and Transition from Elastic-Plastic to
Elastic Propagation Mode", Pisma v ZhETP, 115(2), 80-88 (2022). <br>
<br>
<br>
ID и пароль онлайн-трансляции в Zoom те же, что и для предыдущих
трансляций докладов на Ученом совете:<br>
<div class="moz-cite-prefix"> <a class="moz-txt-link-freetext"
href="https://zoom.us/j/96899364518?pwd=MzBsR2lYT0lYL2x2b1oyNU9LeWlWUT09">https://zoom.us/j/96899364518?pwd=MzBsR2lYT0lYL2x2b1oyNU9LeWlWUT09</a><br>
Meeting ID: 968 9936 4518<br>
Пароль: 250319 </div>
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